In emergency situations, police, firefighters, and other first responders may need to forcibly enter a building or dwelling to gain access in order to save lives. One common method of forcible entry involves forcibly opening a locked door. To master the skill of forcible entry of locked doors, one should have a basic knowledge of various types and doors and security devices that can be encountered in emergency situations, as well as actual training in the forcible entry of locked doors using various types of tools that are utilized for such purpose. One forcible entry technique that is commonly performed in emergency situations is forcible entry of padlocks. A padlock is a type of lock that includes a u-shaped shackle and lock body. The shackle slidably and pivotally moves in relation to the lock body when the padlock is in an “unlocked” state, and the shackle is secured in place by the lock body when the padlock is in a “locked” state.
In general, there are several techniques that are commonly used for removing padlocks in emergency situations. One technique involves the use of a gas-powered circular saw that is equipped with a special circular blade (e.g., aluminum oxide or diamond blade) which is capable of cutting through a portion of a padlock (e.g., cutting the shackle). Another technique for forcible entry of padlocks involves the use of a lock-breaking device to break the shackle from the lock body of the padlock.
For example, FIG. 1A schematically illustrates a conventional lock breaking device (10) which is commonly referred to as a “duck bill” lock breaker. The lock breaking device (10) comprises a rubberized handle (12) and a tapered head (14) (or “duck bill”). The tapered head (14) comprises a wedge portion (16) which comes to a point (18). Another conventional tool that can be used for breaking a padlock is a prying tool referred to as “Halligan” tool. A Halligan tool is a special tool commonly used by firefighters for prying, twisting, punching, or striking For example, FIG. 1B schematically illustrates a conventional “Halligan” tool (11) that is commonly used by firefighters for forcible door entry. The tool (11) includes a claw (or fork) (13), a blade (wedge) (15) (what is commonly referred to as an ADZ end), and a tapered pick (17), which is especially useful in quickly forcing open many types of locked doors.
FIG. 2 schematically illustrates a method for forcibly breaking a padlock (20) using the lock breaking device (10) of FIG. 1A. As shown in FIG. 2, the lock breaking device (10) is manipulated to insert the point (18) of the duckbill head (14) between a lock body (22) and a shackle (24) of the padlock (20). Once the duck bill head (14) is inserted into position, the back of the duckbill head (14) is struck with a head (26) of a flat head axe or a sledge hammer or maul, for example. As the duckbill head (14) is continually struck, the wedge portion (16) of the head (14) is driven further down between the lock body (22) and the shackle (24), which results in incrementally increasing a wedge force between the lock body (22) and the shackle (24). The increasing wedge force ultimately results in separating the shackle (24) from the lock body (22).
Similarly, the Halligan tool (11) of FIG. 1B can be used to break a padlock. For example, to break the padlock (20) shown in FIG. 2 using the Halligan tool (11), the tapered pick (17) can be inserted between a lock body (22) and a shackle (24) of the padlock (20). Once the tapered pick (17) is inserted into position, the top surface of the ADZ end (15) can be repeatedly struck with the head of a flat head axe or a sledge hammer or maul, for example, to break the shackle (24) from the lock body (22). For other forcible entry techniques, the ADZ end (15) or fork end (13) of the Halligan tool (11) can be used to break through the latch of a swinging door by forcing the ADZ end (15) or fork end (13) of the tool (11) between the door and doorjamb and prying the door and doorjamb apart using known techniques.